Propionic acid fermentation by the use of mixed strains of propionic bacteria



Patented June 28, 1932 UNITED STATES PQATENTB OFFICE JAMES M. SHERMAN, 0F ITI-IACA, NEW YORK, ASSIGNQR TO WILBUR WHITE CHEMICAL COMPANY, 01 OSWEGO, NEW YORK, A CORPORATION OF NEW YORK PROPIQNIG ACID FEBMENTAT ION BY THE USE, OF MIXED STRAINS 0F IPROPIONIC BACTERIA No Drawing.

The present invention relates to mixed strains of propionic bacteria, and to a process for the acceleration of propionic fermentation involving the use in admixture of a plurality of strains of the said bacteria.

The invention is based upon my discovery of the fact that the rate of production, and the yield, of propionic acid compounds mcluding propionic acid and propionates by the propionic fermentation of carbohydratecontaining material and/or salts of organlc acids such as for example salts of lactic acid may be increased by the use, in the fermentation procedure, not of a single pure strain of organisms of the type of Bacterium acids propiom'ci but of an admixture or association of aplurality of strains of organisms of the said type. V

In carrying out this improvement I have made use of mixtures e. g'., mixed cultures,containin=g a plurality of varieties of propionic organisms including those varieties which have been described in the literature under the names:

. (1) Baotem'mn acs'di propz om'ci;

S Midi manner, strain ri id Ema-mm M r i, strain al Baotrefium W F strain acterium acid? vprognlom'oi, strain niililfifiw Wartime, ain

Of the above,--(1)', (2')-and (3) are describednby Von Frcudenrich and Orla-Jensen in Landw. J ahrb. Sch-weiz, 20 (1906), 320; (4) is described by Troili-Peterson in Centr. Bakt. Parasitenk., 1909, Abt. 2, 24, 333 (5) is described by Sherman in Jour. Bach, 6 (1921), 379; and 6) is described by Thoni and Alleman in entr. Baht. Parasitenk., 19-10, Abt. 2, 25, 15-30.

I have found that the substitution, in an otherwise ordinary fermentation procedure, of a culture containing all, or a plurality less than all, of the above named varieties of organisms for a culture consisting of but one of the said pure strains, efl'ects an accelera- Application filed May 17, 1928. Serial No. 278,646.

tion of the rate of production of propionic acid, and, as Well, an increase in the yield, from a ferment-able medium. While it is realized that the characteristics of the strains of propionic bacteria hereinbefore mentioned may vary somewhat depending upon the methods of cultivation employed and other envlronmental factors, nevertheless, my invention comprises the use of a culture containpossess substantially equivalent activ' to that of the mixture containing all six 0 the named varieties.

Illustrative of the increased activity of cul tures containing a plurality of strains of f propionic organisms over the activity of cultures containing but a single pure strain thereof: In comparative tests conducted under identical conditions (except of course as to the identity of the fermentation agent), it has been found that, to obtaina concentration of propionic acid of 3%, the fermentation using a culture consisting exclusively of Bacterium acidz' propiom'ci required 5 days, Whereas the same concentration of propionic acid was effected in 4 days or less When using a mixed culture containing 7 Bacterium acz'dz' pro'piom'ci Bacterium a-cz'di propiomci, strain a.

V Bactem'mn acidipropz'om'ci, strain 6 Bacterium acetic" propiomcz', strain 0 Bacterium (midi propionici, strain (1 Bacterium acidi propz'om'cz' rubrum It has been found, further, thatthe abovedescribed propionic fermentation procedure involving the use of a plurality of strains or varieties of the propionic organisms may, with economic advantage as to acceleration of Bacterium a'cz'iiz' propz'om'oi, strain d, and Bactemum ooa'di propiomlca', rubrum to production rate, be by the use there- With of certain organisms which do not of themselves produce propionic acid or propionates but are known to have the capacity of increasing the chemical activity of the said propionic organisms. Such added organisms, the use of which is described in U. S. Patent No. 1,459,959, may for example be selected from one or more of the groups typified by (1) Lactcbacitlus casei and Streptococcus lactic; (2) Proteus vulgaris; and Bacterium alcaligeues.

Again, I have found that the hereinbefore described cultures containing a plurality of strains or varieties of propionic bacteria may with marked success be used in connection with the procedure described in my co-pending application Serial No. 272,863, filed April 25, 1928, which latter consists in effecting propionic fermentative action in the presence of an artificially increased mass of the organisms,particularly, of organisms in a state of physiological youth.

Thus, for example, I have found it advantageous to ferment a suitable medium with a culture containing a plurality of strains of propionic bacteria under such conditions as make possible, during the fermentation operation, the withdrawal of fermented medium and the addition of fresh medium with the retention of a large proportion of the organisms, the mass of retained organisms serving as a mass inoculum for the succeeding charge of fermentable medium, whereby upon repetition the fermentation is initiated quickly and is accelerated in rate, due to the resulting artificially increased mass of organisms.

The retention of organisms in the fermentation zone may, for example, be elfected by carrying out the fermentation in the presence of a finely divided or porous inert substance such as limestone, sand, charcoal, argillaceous material or the like.

It is to be understood that, in inoculating with a plurality of pure strains of propionic organisms, there may be used a mixed culture consisting of or containing the selected strains, or, if found desirable, the selected strains may be separately propagated and thereafter transferred to the fermentation chamber as individual inoculations.

I claim:

1. Process for the production of propionic acid compounds from carbohydrates or other suitable fermentable media by the fermentative action of propionic organisms, characterized by the use of a plurality of strains of organisms of the type of Bacterium acidi prcpiouici.

2. Process for the production of propionic acid compounds from carbohydrates or other suitable fermentable media by the fermentative action of propionic organisms, characterized by the use of a mixed culture containing Bacterium acidi prcpiouici strain a, Bacterium acicZi prcpiouici strain at and Bacterium acidi propicuici rubrum.

3. Process for the production of propionic acid compounds from carbohydrates or other suitable fermentable media by the fermentative action of propionic organisms, characterized by the use of a mixed culture containing Bacterium acidi propicuici, Bacterium acidi prcpicuici strain a, Bacterium acia'i prcpicuici strain Z), Bacterium acidi prcpicuici strain c, Bacterium acicZi pr0- piouici strain ct, and Bacterium acidiprw piouici rubru-m.

4. A composition of matter comprising an admixture of a plurality of pure strains of organisms of the type of B actcrium acidi propicuici in a fermentable medium.

5. A composition of matter comprising a fermentable medium containing in admixture a plurality of pure strains of the organisms Bacterium acidi propiouici strain a, Bacterium acidi prcpiouici strain at and Bacterium acidi propicm'ci rubrum.

6. A composition of matter comprising a fermentable medium containing in admixture pure strains of the organisms Bacterium acicZi prcpiom'ci, Bacterium acidi prepicrtici strain a, Bacterium acidi prcpicuici strain Z), Bacterium acidi propicuici strain 0, Bacterium acicti prcpicuici strain d, and Bacterium acidi propicuici rubrum.

7. Process for the production of propionic acid compounds from carbohydrates or other suitable fermentable media by the fermentative action of propionic organisms, characterized by the use of mixtures consisting essentially of a plurality of pure strains of organisms of the type of B acteriumi acicti pr0- piomci.

8. Process for the production of propionic acid compounds from carbohydrates or other suitable fermentable media by the fermentative action of propionic organisms, characterized by the use of a mixed culture consisting essentially of pure strains of the organisms Bacterium acidi prcpicuici strain a, Bacterium acidi propicnici strain at and Bacteriu/m acidi prcpicuici rubrum.

9. Process for the production of propionic acid compounds from carbohydrates or other suitable fermentable media by the fermentative action of propionic organisms, characterized by the use of'a mixed culture consisting essentially of pure strains of the organisms Bacterium acidi prcpicuici, Bacterium acidi propicuici strain a, Bacterium 'acicZi propiouici strain 6, Bacterium acidi prcpicuici strain 0, Bacterium acidi prcpiouici strain 03, and Bacterium acicZi propieuici rubrum.

In testimony whereof I aflix my signature.

JAMES M. SHERMAN.

'IOG

CERTIFICATE OF CORRECTION.

Patent No. 1,865,146. June 28, 1932.

JAMES M. SHERMAN.

It is hereby certified that the residence of the assignee in the above numbered patent was erroneously described and specified as "Oswego, New York" whereas said residence should have been described and specified as Owego, New York, as shown by the records of assignments in this office; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 1st day oi November, A. D. 1932.

M. J. Moore, (Seal) Acting Commissioner of Patents. 

